DRUG DESCRIPTION

RECOMBIVAX HB Hepatitis B Vaccine (Recombinant) is a
sterile suspension of non-infectious subunit viral vaccine derived from HBsAg
produced in yeast cells. A portion of the hepatitis B virus gene, coding for
HBsAg, is cloned into yeast, and the vaccine for hepatitis B is produced from
cultures of this recombinant yeast strain according to methods developed in the
Merck Research Laboratories.

The antigen is harvested and purified from fermentation
cultures of a recombinant strain of the yeast Saccharomyces cerevisiae containing
the gene for the adw subtype of HBsAg. The fermentation process involves growth
of Saccharomyces cerevisiae on a complex fermentation medium which
consists of an extract of yeast, soy peptone, dextrose, amino acids and mineral
salts. The HBsAg protein is released from the yeast cells by cell disruption
and purified by a series of physical and chemical methods. The purified protein
is treated in phosphate buffer with formaldehyde and then coprecipitated with
alum (potassium aluminum sulfate) to form bulk vaccine adjuvanted with
amorphous aluminum hydroxyphosphate sulfate. Each dose contains less than 1%
yeast protein. The vaccine produced by the Merck method has been shown to be
comparable to the plasma-derived vaccine in terms of animal potency (mouse,
monkey, and chimpanzee) and protective efficacy (chimpanzee and human).

The vaccine against hepatitis B, prepared from
recombinant yeast cultures, is free of association with human blood or blood
products.

All formulations contain approximately 0.5 mg of aluminum
(provided as amorphous aluminum hydroxyphosphate sulfate, previously referred
to as aluminum hydroxide) per mL of vaccine. In each formulation, hepatitis B
surface antigen is adsorbed onto approximately 0.5 mg of aluminum (provided as amorphous
aluminum hydroxyphosphate sulfate) per mL of vaccine. The vaccine contains
< 15 mcg/Ml residual formaldehyde. The vaccine is of the adw subtype.

What are the precautions when taking hepatitis b vaccine (recombinant) (Recombivax)?

Before getting hepatitis B vaccine, tell your doctor or pharmacist if you are allergic to it; or to yeast; or other vaccines; or if you have any other allergies. Some vials and prefilled syringes may use latex rubber stoppers or plungers. Tell your doctor if you are allergic to latex. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.